Title

Author

Date of Award

Degree Type

Degree Name

School

School of Exercise and Health Sciences

Faculty

Health, Engineering and Science

First Advisor

Professor Ken Nosaka

Second Advisor

Dr. Chris Abbiss

Third Advisor

Associate Professor Anthony Blazevich

Abstract

A typical badminton singles match involves numerous intense and high impact movements. Lunges were accounted for approximately 15% of overall movements and were believed to presumably induce significant muscle damage following a match. However, no previous study has investigated changes in knee extensor muscle function after a badminton match.The present study investigated changes in knee extensor neuromuscular function and muscle soreness after a simulated 1-h badminton singles match in relation to the number of lunges performed in the match.

Ten state-level male badminton players were recruited (n=10), with each player played a total of eight simulated 1-h matches under the International Badminton World Federation rules. However, each participant was required to play against the same opponent twice and only one participant was fitted with the equipment at any one session, thus the total number of matches analysed was 40. The number of lunges performed by each player in a game was obtained from video analysis. Heart rate (HR) and core body temperature were recorded during the matches, and blood lactate (BL) was measured before and immediately post match. Both femoral nerve and muscle electrical stimulations were used in the present study. Maximal voluntary isometric contraction (MVC) torque of the knee extensors and flexors, voluntary activation during the knee extension MVC (VA), torque generated by a doublet (DT), and 20 Hz (T20) and 80 Hz stimulation (T80) and the ratio (T20/T80) for the knee extensors, and muscle soreness of knee extensor muscles by a 100-mm visual analog scale (VAS) were measured before, immediately (8 - 10 min post-match), 1-h and 24-h after a match. Pearson product-moment correlations were computed to examine relationships between variables using ANOVA.Average (± SD) match HR was 162.0 ± 11.0 bpm, post-match BL was 7.2 ± 1.3 mM.L-1, and 194 ± 18 lunges were performed per match per player. Core body temperature increased from 36.5 ± 0.5 oC to 39.4 ± 0.5 oC immediately post match. Knee extension MVC torque was lower than baseline (278.4 ± 50.8 Nm) at immediately (-11%) and 1 h (-14%) post match (P

Moderate muscle soreness developed after 1-h simulated badminton matches, but muscle function returned to baseline by 24 hour post match, indicating moderate muscle fibre damage. Since VA was decreased without changes in T20/T80, and knee flexion MVC torque also showed similar changes to those of knee extension MVC torque that was thought to be affected by lunges, the decrease in MVC torque appeared to be associated with central rather than peripheral fatigue or muscle damage. With moderate muscle soreness developing after 1-h simulated badminton matches and muscle function returning to baseline by 24 hour post-game, suggesting minimal muscle fibre damage. It was concluded that both central and peripheral factors contributed to alterations in neuromuscular fatigue and that muscle damage was moderate after the singles matches in which the game intensity and physiological characteristics were close to those in competitive tournaments.